Application

The cables are designed for use as subscriber distribution cables and as connection between central offices. The cables are suitable for installation in ducts, direct burial in the ground and also for aerial installation with integral suspension strand. An armoured option is offered for direct burial installations. A figure-8 self support option is offered for aerial installation.

Standards

Telcordia (Bellcore) GR-421

Construction

Conductors : Solid annealed bare copper, 0.4/0.5/0.63/0.9mm, as per ASTM B-3/class 1 of IEC 60228.

Insulation : Solid medium or high density polyethylene as per ASTM D 1248/IEC 60708.

Twisted Pairs : Insulated conductors are twisted into pairs with varying lay length to minimize crosstalk.

Cabling Element : Twisted Pairs.

Cable Core Assembly : Cables with up to 400 pairs are composed of 25-pair units or 12/13-pair units; cables with over 400 pairs are composed of 50 or 100-pair units. Any extra pairs form a separate unit. Units are identified by colour coded binders. Construction is per GR-421 given in Cable Make Up Diagram.

Core Wrapping : One or more non-hygroscopic polyester tapes are helically or longitudinally laid with an overlap. These tapes furnish thermal, mechanical as well as high dielectric protection between shielding and individual conductors.

Moisture Barrier : A layer of aluminium tape (0.2mm) coated with PE-copolymer is applied longitudinally with overlap over the cable core to provide 100% electrical shielding coverage and ensures a barrier against water vapor. In cables with more than 200 pairs, the aluminum tape may be corrugated for improved cable flexibility.

Sheath : Black low density polyethylene as per ASTM D 1248/IEC 60708, being able to withstand exposure to sunlight, temperature variations, ground chemicals and other environmental contaminants.

Ripcord : Ripcord may be provided for slitting the sheath longitudinally to facilitate its removal.

Spare Pairs (optional) : Spare pairs may be incorporated for large pair cables.

Continuity Wire (optional) : One tinned copper drain wire may be longitudinally laid to ensure electrical continuity of the screen.

Optional Construction

Armoured Cable : 0.15mm thick corrugated steel tape armour is applied with an overlap over an optional inner polye-thylene sheath. An outer polyethylene sheath is applied over the armour.

Self-Support Cables : A 7-strand galvanized steel strand is used as support wire. Black polyethylene sheath covers both core and support wire in a figure-8 construction.

Aabbreviations

LAP (CAP) : Bare Aluminium tape + PE sheath

LAPSP (CAPSP) : LAP sheath + steel tape armour + PE sheath

LAP (ALPETH) : PE sheath

PAP : PE inner sheath + bare aluminium tape + PE sheath

PASP : PE inner sheath + bare aluminium tape + steel tape armour + PE outer sheath

ASP (STAPETH) : Bare aluminium tape + steel tape armour + PE outer sheath

CACSP : Copolymer coated aluminum tape + copolymer coated steel tape armour + PE outer sheath

LAPSP : Copolymer coated aluminum tape +PE inner sheath + steel tape armour + PE outer sheath

FIGURE 8 LAP : Copolymer coated aluminum tape + PE outer sheath + self supporting

Electrical Properties

MECHANICAL AND THERMAL PROPERTIES

Temperature range during operation (fixed state) : -30°C – +70°C

Temperature range during installation (mobile state) : -20°C – +50°C

Minimum bending radius : 10 × Overall Diameter (unarmoured cables); 15 × Overall Diameter (armoured cables)

COLOUR CODE

Standard colour code is per GR-421 given in Colour Code Chart

DIMENSIONS AND WEIGHT

Solid PE Insulated and LAP Sheathed (ALPETH) Air Core Cable to GR-421

Fig 8 Solid PE Insulated & LAP Sheathed (Alpeth) Air Core Cable to GR-421

Solid PE Insulated & PAP Sheathed Air Core Cable to GR-421